Acoustics - Determination of acoustic properties in impedance tubes - Part 2: Two-microphone technique for normal sound absorption coefficient and normal surface impedance (ISO 10534-2:2023)
This test method covers the use of an impedance tube, two microphone locations and a frequency
analysis system for the determination of the sound absorption coefficient of sound absorbing materials
for normal incidence sound incidence. It can also be applied for the determination of the acoustical
surface impedance or surface admittance of sound absorbing materials. As an extension, it can also be
used to assess intrinsic properties of homogeneous acoustical materials such as their characteristic
impedance, characteristic wavenumber, dynamic mass density and dynamic bulk modulus.
The test method is similar to the test method specified in ISO 10534-1[1] in that it uses an impedance
tube with a sound source connected to one end and the test sample mounted in the tube at the other
end. However, the measurement technique is different. In this test method, plane waves are generated
in a tube by a sound source, and the decomposition of the interference field is achieved by the
measurement of acoustic pressures at two fixed locations using wall-mounted microphones or an in-
tube traversing microphone, and subsequent calculation of the complex acoustic transfer function and
quantities reported in the previous paragraph. The test method is intended to provide an alternative,
and generally much faster, measurement technique than that of ISO 10534-1[1].
ΚΩΔΙΚΟΣ ΠΡΟΪΟΝΤΟΣ:
CYS EN ISO 10534-2:2023
This test method covers the use of an impedance tube, two microphone locations and a frequency
analysis system for the determination of the sound absorption coefficient of sound absorbing materials
for normal incidence sound incidence. It can also be applied for the determination of the acoustical
surface impedance or surface admittance of sound absorbing materials. As an extension, it can also be
used to assess intrinsic properties of homogeneous acoustical materials such as their characteristic
impedance, characteristic wavenumber, dynamic mass density and dynamic bulk modulus.
The test method is similar to the test method specified in ISO 10534-1[1] in that it uses an impedance
tube with a sound source connected to one end and the test sample mounted in the tube at the other
end. However, the measurement technique is different. In this test method, plane waves are generated
in a tube by a sound source, and the decomposition of the interference field is achieved by the
measurement of acoustic pressures at two fixed locations using wall-mounted microphones or an in-
tube traversing microphone, and subsequent calculation of the complex acoustic transfer function and
quantities reported in the previous paragraph. The test method is intended to provide an alternative,
and generally much faster, measurement technique than that of ISO 10534-1[1].